I have had some heated discussions (disagreements!) with a fellow member regarding this issue. I believe it deserves a discussion of its own.
If there are similar threads, or it has already been discussed to death, I apologize, please point me to them.
There are sensitivity values given for headphones, it is given as dB for 1mW or dB for 1V RMS.
The general attitude, and a mathematical one! Is, to use this figure and calculate, how much power is needed to achieve a healthy loudness of say 115dB. Then we can safely say, this headphone needs an amp that can produce this much power.
Straight forward, makes sense! No?
I say No!
And that is the gist of my disagreement with my fellow member.
My arguments against:
- First see this
I have stated among my many arguments previously, that measurements for Electronic devices (DACs, Amps) can be absolute, but when it comes to Transducers, it is not.
Firstly we should recognize that, the sensitivity values given, are just an indication-tool, used for comparison.
Take two headphones for example, one has a dip in its FR curve at 400Hz, the other has a peak at the same frequency. Do you think if I pick 400Hz to measure the sensitivity, the value I get, is going to be reliable?
Secondly, in the scope of calculating how much power is needed, Loudness is a subjective value.
It depends on the type of music being played, the FR of the DUT, aaaand . . . , the hearing of the listener's ears.
Power and Gain are also inter-related. Higher power amps have more gain, and sometimes, we may need the gain, and not necessarily the max. power. With headphones, people equalize. If you equalize Bass frequencies, you need to use pre-cuts, right?
The amp being used, can quickly run out of power at bass, and overall loudness suffers. Now what if we didn't EQ the bass, but we EQ the mids up? Now we don't need to use a pre-cut, Our ears are sensitive to the mids, so the headphones will become louder with the same power capability.
Finally, someone with a failing hearing, will need more power to Hear better.
So I state that calculating (guessing) power requirement for headphones, is not as straight forward as some believe. It is complex, with variables depending on case to case surroundings.
What do you think?
If there are similar threads, or it has already been discussed to death, I apologize, please point me to them.
There are sensitivity values given for headphones, it is given as dB for 1mW or dB for 1V RMS.
The general attitude, and a mathematical one! Is, to use this figure and calculate, how much power is needed to achieve a healthy loudness of say 115dB. Then we can safely say, this headphone needs an amp that can produce this much power.
Straight forward, makes sense! No?
I say No!
And that is the gist of my disagreement with my fellow member.
My arguments against:
- First see this
I have stated among my many arguments previously, that measurements for Electronic devices (DACs, Amps) can be absolute, but when it comes to Transducers, it is not.
Firstly we should recognize that, the sensitivity values given, are just an indication-tool, used for comparison.
Take two headphones for example, one has a dip in its FR curve at 400Hz, the other has a peak at the same frequency. Do you think if I pick 400Hz to measure the sensitivity, the value I get, is going to be reliable?
Secondly, in the scope of calculating how much power is needed, Loudness is a subjective value.
It depends on the type of music being played, the FR of the DUT, aaaand . . . , the hearing of the listener's ears.
Power and Gain are also inter-related. Higher power amps have more gain, and sometimes, we may need the gain, and not necessarily the max. power. With headphones, people equalize. If you equalize Bass frequencies, you need to use pre-cuts, right?
The amp being used, can quickly run out of power at bass, and overall loudness suffers. Now what if we didn't EQ the bass, but we EQ the mids up? Now we don't need to use a pre-cut, Our ears are sensitive to the mids, so the headphones will become louder with the same power capability.
Finally, someone with a failing hearing, will need more power to Hear better.
So I state that calculating (guessing) power requirement for headphones, is not as straight forward as some believe. It is complex, with variables depending on case to case surroundings.
What do you think?
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